Free radicals scavenging, acetylhydrolase inhibition and antimicrobial activity of aromatic plant hydrolate mixtures

This study aimed to investigate the free radicals scavenging, inhibition of acetylhydrolase and antimicrobial activity of five mixtures of hydrolates obtained by hydrodistillation of Lamiaceae plants, Rosmarinus officinalis , Salvia officinali s and Lavandula angustifolia . Chemical composition of hydrolates was analysed by gas chromatography coupled with mass spectrometry for volatiles and UV-VIS spectrophotometry for total phenolic and flavonoid content. The results of free radicals scavenging and acetylhydrolase inhibition activity have shown improved effect of selected hydrolates mixtures, compared to individual hydrolates. The effect was in accordance to their polyphenolic content, indicating synergistic action of the combined biologic active compounds from different extracts of rosemary, sage and lavender. In turn, the antimicrobial activity of hydrolates mixtures was similar to that of individual hydrolates in Staphylococcus aureus , Pseudomonas aeruginosa and Rhizoctonia solani cultures, revealing no synergistic effect of volatiles, as mainly responsible compounds. In conclusion, selected mixtures of aromatic plant hydrolates can provide added value to these by-products through further development of natural pesticide and/or fungicide products useful for the ecological crop protection.